Ph changing greatly?

Question

-------------------------I actually do frequent water changes but for some reason there was more than two or three times as much waste as usual . I measured the ph straight from my tap the other day and it was over 8.5 when it is usually around 7.2. We have had severe flooding lately and was wondering if this may be the reason for the change in ph.

Followup To

Question -
Hi Karen. I have been keeping fish for somewhere around a year. Yesterday when changing my water for my 30 gallon tank i noticed that their seemed to be very excessive waste on the bottom of the tank and one of my fish has cloudy eye. I did a ph test and my ph had gone from 7.2 to 8.2 in one week this has never happened before. I recently added rocks and driftwood(both natural) to my tank and i was wondering if they could of caused this? Also i was wondering if you knew whick rocks were harmful to fish so i can identify them.

Answer -
Dear Derek,
Cloudy eyes and waste on the bottom of the aquarium are both warning signs that your aquarium may be very highly polluted. I would begin insuring to vacummn the gravel along with doing a water change everyday at 30% or more. Make sure your filter(s) are clean but be sure to only rinse he sponges in a bucket of aquarium water.

~You'll certainly have to investigate why your aquarium is as dirty as it is. Perhaps overfeeding, or lack of gravel vacummings and water changes. Or maybe just very messy fish. Definately please try to double your gravel vacumming and water changing schedule.

A pH that rises from 7.2 to 8.2 couldn't be from the driftwood, (which naturally releases tannic acid into the water that lowers the pH) But your rocks certainly could and they may be the culprit, although most all aquairums rocks are safe for your fish in one sense, many can release minerals into your aquarium water that raises both pH and hardness levels to sometimes great levels. One good way to know is to place one of those rocks in a bucket of water--test the pH before placing the rock in and then a week after, of course if the pH changes then you know that must be the problem. Some of the types of rocks that can release minerals and raise your pH (also known as Calcareous rocks) are; Chalk, limestone, Marble, and Tufa, and most rocks whom have several holes are often Calcareous. The holes are caused by the erosion of brittle calcareuous substances within the rock.  If you have found your rocks to be unsafe, some calcareous rocks will fizz when vinegar is placed on them and watched if it fizzes, this isn't always a tell-all indication and perhaps the best test is placing it in some water and testing the pH before and a week after placing the rock in.

Keep in mind safe rocks that are inert are Coal, Basalt, Flint, Granite, Sandstone, Quartz, Slate, and lava rock.

I really hope this helps!
Best wishes and Happy fishkeeping!
Karen~

Answer
A big hello again!
Excessive waste could be from a clogged filter. I would insure to keep your filter running smoothly and you might have to increase your water changes due to perhaps a high bioload. You must help the little fish with cloudy eyes get well, and the best way to do that is very frequent water changes.

I would suspect the flooding to be part of your high pH problem. Unfortunately this is something i've never experienced. Just be careful if you do water changes that the tap water's pH is not drastically different from your aquarium's.

Best wishes as always,
I hope your pH gets straightened out soon!
Karen~